• Kyungpook Mathematical Journal
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• v.60 no.2
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• pp.297-305
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• 2020

We show that selfadjoint operator extensions of minimal second order difference operators have only discrete spectrum when the odd order coefficient is unbounded but grows or decays according to specific conditions. Selfadjoint operator extensions of minimal differential operator under similar growth and decay conditions on the coefficients have a absolutely continuous spectrum of multiplicity one.

• Water for future
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• v.17 no.3
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• pp.211-219
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• 1984

A 4-level baroclinic numerical model is designed by using the vorticity equation and Omega equation. Block-Cyclic-Reduction method is applied to the solution of the Helmholtz defferential equation, which is proved to be better than the Relaxation method from the composite viewpoint of accuracy, stability and economy. It was investigated whether the model explains the physical process influenced by voricity and temperature advection. It was also examined if the model atmosphere describes the general circulation. This examination is similar to Phillips(1956). The result of this numerical experiment shows that the model explains qualitatively the Quasi-Geostrophic theory for the development of Baroclinic wave, as throughly described in Holton(1972).

• Journal of the Korean Society for Nondestructive Testing
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• v.11 no.2
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• pp.7-14
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• 1991

The integral model for the eddy current phenomena has been suggested. The model could lift the limitations of the previously well-known analytical model of eddy current theory. The model could be applied to two-dimentional, arbitary shaped defects. The computer programs have been developed in order to calculate the eddy current signal with the suggested integral method. The eddy current signals by the model calculations have been shown similar patterns to the actual experimental data from the real defects in the calibration standard tubes.

• Korean Journal of English Language and Linguistics
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• v.3 no.1
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• pp.89-108
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• 2003

As pronouns are resolved with their antecedents, definite NPs may enter into the anaphora-antecedent relations with indefinite NPs. This paper is to provide faster and more efficient computational algorithms by which definite NPs are resolved effectively, For this purpose, this paper extends Chierchia's Binding Theory in Categorial Grammar, and definite NPs are resolved with their antecedents by similar algorithms that are used to reflexive resolution. In these algorithms, the relations between indefinite NP and definite NP are represented with λ-expressions, and definite NPs are resolved with their antecedent by λ-conversions.

• Korean Journal of Mathematics
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• v.18 no.4
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• pp.465-472
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• 2010

In this paper, we investigate the extent of the set on which the modulus of a meromorphic function is lower bounded by a term related to some Nevanlinna Theory functionals. A. I. Shcherba estimate the size of the set on which the modulus of an entire function is lower bounded by 1. Our theorem in this paper shows that the same result holds in the case that the lower bound is replaced by$lT(r,f)$, $0{\leq}l$ < 1, which improves Shcherba's result. We also give a similar estimation for meromorphic functions.

• Journal of the Korean Mathematical Society
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• v.42 no.1
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• pp.17-35
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• 2005

Necessary conditions for a deterministic optimal control problem which involves states constraints are derived in the form of a maximum principle. The conditions are similar to those of F.H. Clarke, R.B. Vinter and G. Pappas who assume that the problem's data are Lipschitz. On the other hand, our data are not continuously differentiable but only differentiable. Fermat's rule and Rockafellar's duality theory of convex analysis are the basic techniques in this paper.

• Journal of the Korean Mathematical Society
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• v.33 no.4
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• pp.709-716
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• 1996

Nielsen coincidence theory is concerned with the determinatin of a lower bound of the minimal number MC[f,g] of coincidence points for all maps in the homotopy class of a given map (f,g) : X $\to$ Y. The Nielsen Nielsen number $N_R(f,g)$ (similar to [9]) is introduced in [3], which is a lower bound for the number of coincidence points in the relative homotopy class of (f,g) and $N_R(f,g) \geq N(f,g)$.

• Journal of the Korean housing association
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• v.5 no.2
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• pp.1-14
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• 1994

This study was made to analyze the housing adjustment patterns of Korean families through the Microsociological approach. General research model used in this study was similar to that used in the previous study (Hong. 1986. 1992. 1993. 1994), which is a modified version of housing adjustment theory developed by Morris and Winter(1978). In short this study was made to analize the housing adjustment pattern not in terms of external devision and uniformity but in terms of diversity and individuality of each family.

• Bulletin of the Korean Mathematical Society
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• v.54 no.4
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• pp.1173-1183
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• 2017

We give some sufficient conditions for the null and infinite derivatives of the $Riesz-N{\acute{a}}gy-Tak{\acute{a}}cs$ (RNT) singular function. Using these conditions, we show that the Hausdorff dimension of the set of the infinite derivative points of the RNT singular function coincides with its packing dimension which is positive and less than 1 while the Hausdorff dimension of the non-differentiability set of the RNT singular function does not coincide with its packing dimension 1.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1360-1362
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• 1999

This paper describes the fault location technique using wavelets in transmisson line. Estimation of fault location is performed using synchronized data sampled at two ends of line and travelling wave. The similar current wave modeled in PSCAD/EMTDC and MATLAB was applied to evaluate the accuracy of theory proposed in this paper. The results of fault location shown in this paper will be evaluated as an effective suggestion for fault location in real transmisson line